标题： 新活跃小行星2010 LH15的物理性质 显示英文标题

标题： Physical properties of newly active asteroid 2010 LH15

摘要： 主带小行星2010 LH$_{15}$被归类为活跃小行星，这是基于最近从2010年和2019年的档案图像中发现的尘埃活动。 在本研究中，我们使用ZTF在2019年7月26日至8月31日期间的档案数据，对活跃小行星2010 LH$_{15}$的尘埃尾进行测量和动力学建模，这些相对独立方法得出的物理特性是一致的。 测光结果表明，核的半径为$1.11\pm0.02$千米，假设几何反照率为$p_r = 0.05$，核的颜色指数与核周围的抛射物较为接近，值为$H_g - H_r = 0.44\pm0.07$。 有效散射截面在整个观测期间以平均速率$0.28\pm0.02$ km$^2$ day$^{-1}$增加，表明 LH$_{15}$的活动可能由能够引起如升华这样的持续过程的机制驱动。 进一步的尘埃动力学建模表明，尘埃活动早在2019年6月26日左右就开始了，喷出的尘埃粒子半径范围从0.03毫米到3毫米。 终端速度与尘埃大小的依赖关系与升华驱动的机制一致。 如果 LH$_{15}$的轨道是稳定的，其升华起源将使主小行星带中含水冰区域的内边界向内扩展约0.1 AU。 显示英文摘要

摘要： Main-belt asteroid 2010 LH$_{15}$ has been classified as an active asteroid, based on the recent discovery of dust activity from the archival images observed in 2010 and 2019. In this study, we perform measurements and dynamical modeling of the dust tail of the active asteroid 2010 LH$_{15}$ using ZTF archival data from July 26 to August 31, 2019, with the derived physical properties from these relatively independent methods being compatible. The photometric results show that the radius of the nucleus is $1.11\pm0.02$ km with assumed geometric albedo of $p_r = 0.05$, and the color index of the nucleus is relatively close to that of the ejecta around the nucleus, with a value of $H_g - H_r = 0.44\pm0.07$. The effective scattering cross-section increases at an average rate of $0.28\pm0.02$ km$^2$ day$^{-1}$ throughout the observation period, indicating that the activity of LH$_{15}$ is likely driven by mechanisms capable of causing a sustained process like sublimation. Further dust dynamics modeling indicates that the dust activity initiates as early as about 26 June 2019, with the ejected dust particles having a radius ranging from 0.03 mm to 3 mm. The dependence of the terminal velocity on dust size is consistent with a sublimation-driven mechanism. If the orbit of LH$_{15}$ is stable, its sublimation origin will extend the inner boundary of the water-ice-bearing region in the main asteroid belt inward by approximately 0.1 AU.